Therapeutic equivalence: fallacies and falsification
Abstract
The number of studies designed specifically to demonstrate therapeutic equivalence or alternatively non‐inferiority of pharmaceutical treatments has increased dramatically in recent years, during which time awareness of the methodological issues has increased. Regulatory authorities have been quick to recognize the need for specific support and have either published or initiated the creation of relevant guidance. Common misconceptions prevail however regarding sample size estimation and the choice of the most appropriate patient population to analyse while other areas such as equivalence margin specification and covariate adjustment have been neglected. This paper challenges some of the regulatory advice and the interpretation that others have made of this guidance with the aim of stimulating further debate. Copyright © 2003 John Wiley & Sons, Ltd.
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Regulatory issues frequently also have to be considered in determining the equivalence margin.
“Frequently, regulatory issues also have to be considered 5 .”
From Understanding Equivalence and Noninferiority Testing (2011) · cites this paper as [5]
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Sample size calculations for ordered categorical data
Whitehead, J. (1993) · Statistics in Medicine · doi:10.1002/sim.4780122404 · Cited by 297 · see citing works
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Understanding Equivalence and Noninferiority Testing
Walker, E., & Nowacki, A. S. (2011) · Journal of General Internal Medicine · doi:10.1007/s11606-010-1513-8 · Cited by 751 · see citing works
Methodology of superiority vs. equivalence trials and non-inferiority trials
Christensen, E. (2007) · Journal of Hepatology · doi:10.1016/j.jhep.2007.02.015 · Cited by 205 · see citing works
- Authors
- Garrett, A. D.
- Affiliations
- IQVIA (United Kingdom) (GB)
- Corresponding author
- Garrett, Andrew D.
- ORCID
- Garrett, Andrew D.
- Venue
- Statistics in Medicine
- Publisher
- Wiley
- Published
- 2003-02-05
- Volume
- 22
- Issue
- 5
- Pages
- 741-762
- ISSN
- 0277-6715 (ISSN-L)
- 1097-0258
- OpenAlex
- W2172036897
- Cited by
- 88
- References
- 1
- Citations by year
- 2026: 1 · 2025: 2 · 2024: 1 · 2023: 3 · 2022: 3 · 2021: 6 · 2020: 2 · 2019: 3 · 2018: 4 · 2016: 4 · 2015: 3 · 2014: 8 · 2013: 4 · 2012: 4
- FWCI
- 3.75
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Statistics in Medicine (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
- Life Sciences › Immunology and Microbiology › Immunology › Biosimilars and Bioanalytical Methods
- Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Pharmaceutical studies and practices
- Keywords
- therapeutic equivalence, sample size determination, equivalence margin, covariate adjustment, regulatory guidelines, methodological issues, generic drug comparison
- MeSH terms
- Drug Evaluation, Humans, Research Design, Therapeutic Equivalency, Models, Statistical, Odds Ratio, Randomized Controlled Trials as Topic, Sample Size
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